Technology is playing a central role within health care and the use of systems such as patient portals of electronic medical records (EMRs) are becoming more widespread. The use of EMRs will continue to gain popularity as patient involvement in disease prevention, management, and decision-making becomes more emphasized within our health care system. Unfortunately, many of these systems have been designed without consideration of the needs and characteristics of diverse user groups and have increased the complexity of the demands associated with health care engagement. This is problematic for many patient populations, especially those with lower cognitive abilities or health literacy. Health literacy has been demonstrated to have a significant impact on important health-related issues such as an individual's ability to make use of preventative health services, communicate effectively with his or her physician, and understand information critical to managing his or her health. Older adults are an especially vulnerable group due to age-related declines in cognition and an increased likelihood of low health literacy. This is problematic as older people are among those most likely to be in need of and seek medical care. Thus, it is critically important to understand the extent to which older adults, especially those with low health literacy, can use e-health applications such as patient portals of EMRs, and also to understand the factors that influence their successful use of these systems. The aims of this proposed project are to: 1) examine the ability of middle-aged and older adults to use a patient portal of an EMR to perform common health management tasks;2) examine the relationships between individual characteristics such as age, cognitive abilities, and health literacy, and the performance of health management tasks using a patient portal;and 3) identify usability problems inherent in the use of patient portals and identify initial design solutions. The study will involve 80 adults aged 40-85 years with both low and high health literacy levels [as measured by the Test of Functional Health Literacy in Adults (TOFHLA)]. Using a fictitious patient medical record on a simulated EMR portal, subjects will be evaluated on their ability to perform three common health management tasks: 1) medication management;2) review and interpretation of lab/test results;and 3) health maintenance activities. Measures will include objective measures of performance and assessments of usability. Ultimately, data from this study will yield important information about aging, cognition, health literacy and the use of health information technology, which is currently lacking in the available literature. This study will help fulfill the mission of the AHRQ to improve the effectiveness of health care for Americans as the outcomes from this study can be used to guide the development of future EMR systems so that diverse older adult populations can be more empowered in managing their health. Furthermore, the target population is an AHRQ priority population and the outcomes of the proposed study can be used to enhance the quality of care for those who are in the most need and Impact The focus of the study is on the ability of middle-aged and older adults with both low and high levels of health literacy to use a patient portal of an electronic medical record (EMR) to perform common health management tasks. This is important as most older adults have at least one chronic condition, are in need of health care more than other groups, and may have more difficulty using an EMR especially if they have low health literacy. The goal is to identify design interventions that will help adults especially those with low levels of health literacy to use a patient portal of an EMR to accomplish health management tasks.